This invention relates to rotary internal combustion engines and more particularly to improvements in the structure thereof.
Internal combustion rotary engines are well known which provide a power rotor which rotates about its center and has spring-loaded sliding vanes thereon which contact the adjacent interior surface of the stator housing at all times as they sweep through an arcuate compression and expansion chamber defined therein. In such an engine, each vane sweeps through the compression chamber to compress a fuel-air mixture therein and then the compressed mixture is transferred in some manner by a rotary transfer valve to the trailing side of the vane in the expansion chamber where it is ignited to cause the vane to drive the rotor. The rotary transfer valves heretofore proposed for such purpose have not been entirely satisfactory. There is thus a need in such a rotary internal combustion engine to provide an improved rotary transfer valve mechanism which can be more readily controlled to transfer a compressed fuel-air mixture in a reliable manner from the leading side to the trailing side of each vane as it advances from the compression chamber into the expansion chamber.
In accordance with the present invention, a power rotor is secured to drive a shaft so as to rotate in a stator cavity of a housing. The power rotor includes two spring-loaded vanes seated in diametrically opposed radial slots. The internal surface of the stator cavity in the housing is generally ovally shaped in that it is provided on one side thereof with a segment portion defining on the interior surface thereof an inwardly directed tip and provided on the opposite side thereof with an inwardly curved wall portion defining on the interior surface thereof a crest. The sealing contact of the periphery of the rotating rotor with the tip and crest divide the circumferential space provided between the rotor and the interior surface of the cavity into two arcuate chambers, a compression chamber and an expansion chamber.
Included in the housing for the power rotor and located on the side of the stator cavity therefor is an additional cavity the cylindrical internal surface of which is formed in part by the exterior surface of the inwardly curved wall portion provided on the side of the stator cavity. A rotary transfer valve is secured on a shaft to rotate in the additional cavity. The rotary transfer valve is in the form of a cylindrical plug having generally U-shaped pockets on diametrically opposed sides thereof and having its periphery sealingly contacting the cylindrical interior surface of the additional cavity as it rotates therein.
The side segment portion of the stator housing is provided with an intake passage leading into the front end of the arcuate compression chamber and an exhaust passage leading out of the rear end of the arcuate expansion chamber. The curved wall portion which is common to the sides of the cavities for the power rotor and the rotary transfer valve is provided with a transfer inlet port leading out of the rear end of the compression chamber and a transfer outlet port leading into the front end of the expansion chamber.
A cam wheel assembly including a backside cam wheel and a frontside cam wheel is secured to the drive shaft of the power rotor. A follower in the form of a timing wheel is secured to the shaft of the rotary transfer valve. The timing wheel has two diametrically opposed notches on the periphery thereof which are respectively aligned to be positioned adjacent the leading edge of the two pockets on the rotary transfer valve. The cam wheel assembly has two diametrically opposed initiating pins provided on the back surface thereof for respectively engaging the two notches on the timing wheel to intermittently rotate the rotary transfer valve. The timing wheel also has two sets of pins on the surface thereof which are positioned so as to be engaged by recesses and notches provided on the peripheries of the two rotating cam wheels so as to further control the intermittent rotary action of the rotary transfer valve in relation to the rotating of the two vanes.
A fuel-air mixture introduced into the compression chamber through the intake passage is compressed by one of the vanes and transferred to one of the pockets of the rotary transfer valve which is positioned opposite the transfer inlet port by the action of the cam wheel assembly. The rotary transfer valve is then rotated by the action of the cam wheel assembly such that the pocket is initially positioned between the transfer inlet port and the transfer outlet port where it momentarily remains stationary while the vane continues to rotate. As a result, upon the pocket on the rotary transfer valve being positioned by the action of the cam wheel assembly opposite the transfer outlet port it delivers the quantity of compressed fuel-air mixture therein into the front end of the expansion chamber behind the vane. Upon the pocket being further moved by the action of the cam wheel assembly beyond the transfer outlet port, a spark plug positioned in the wall of the stator housing fires to explode the fuel-air mixture and drive the vane through the expansion chamber, the exhaust gases resulting from the explosion being forced out of the exhaust passage by the rotation of the following vane.
Accordingly, one of the objects of the present invention is to provide an improved rotary transfer valve mechanism for a rotary internal combustion engine which provides for transferring a compressed quantity of fuel-air mixture from the leading to the trailing side of a vane during the operation thereof.
Another object of the present invention is to provide cam means synchronized to rotate with a power rotor having sliding vanes on diametrically opposed slots of the periphery thereof for intermittently controlling the rotation of a rotary transfer valve having pockets on diametrically opposed portions of the periphery thereof so as to enable each pocket to transfer a fully pressurized fuel-air mixture from the leading side to the trailing side of a vane as the vane advances from the compression chamber to the expansion chamber of a rotary internal combustion engine.
Yet another object of the present invention is to provide a cam wheel assembly keyed to the shaft of the power rotor of a rotary internal combustion engine for intermittently controlling the rotation of a timing wheel keyed to the shaft of a rotary transfer valve to provide for a quantity of compressed fuel-air mixture to be transferred by a pocket on the periphery of the rotary transfer valve from the leading side to the trailing side of a vane on the rotor.
With these and other objects in view, the invention consists of the construction, arrangement and combination of the various parts of the device whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustrated in the accompanying drawings.